OBJECTIVETo assess the accuracy of immunological fecal occult blood test (iFOBT) for detection of colorectal cancer (CRC).

METHODSA total of 1 197 studies published before June 2014 were selected from PubMed and Embase and 17 of which were finally included in this meta-analysis. A bivariate mixed-effects models was used for overall value merging and heterogeneity testing. In addition to the overall sensitivity and specificity, the analyses were also performed among certain subgroups, including a "colonoscopy group" (all were referred for colonoscopy diagnosis regardless screening results) and a "follow-up group" (only the screening positive were referred and all were then followed up), a qualitative group and a quantitative group (classified by the way of iFOBT result reading).

RESULTSA total of 161 502 subjects aged from 48 to 63 years were included in the analysis. IFOBT had an overall integrated sensitivity of 0.85 (95% CI: 0.79-0.89) (heterogeneity test: Q = 59.67, P < 0.001) and an overall integrated specificity of 0.93 (95% CI: 0.92-0.94) (heterogeneity test: Q = 1 722.53, P < 0.001) for detection of CRC. In the subgroup analysis, it was found that in the "colonoscopy group" and in the "follow-up group", the sensitivity were 0.81 (95%CI: 0.73-0.87) and 0.88 (95% CI: 0.81-0.92), respectively; the specificity were 0.92 (95% CI: 0.89-0.93) and 0.95 (95% CI: 0.94-0.96), respectively. It was also found that in the qualitative group and the quantitative group, the sensitivity were 0.84 (95% CI: 0.76-0.90) and 0.86 (95% CI: 0.78-0.92), respectively; the specificity were 0.94 (95% CI: 0.91-0.96) and 0.93 (95% CI: 0.91-0.94), respectively.

CONCLUSIONIFOBT had high overall sensitivity and specificity for detecting colorectal cancer.